Archive for the ‘bacterial infections’ Category

What else can a strep infection lead to?

Saturday, December 24th, 2011

tiny bacteria can lead to huge consequences

I wash my hands more frequently these days, not as a sign of OCD, but just from common sense. Familiar bacteria, ones that some of us carry and that our school-age kids may encounter several times a year, can rarely cause horrendous, life-threatening problems. WebMD has a short review of one of these diseases, one that physicians call necrotizing fasciitis (NF), but most non-medical folk know of as "Flesh-eating Strep."

I had read about this complication of the same bacteria that can cause strep throat, but prior to moving to Fort Collins in 1999, had never known of someone who developed it. Then, shortly after arriving here we joined the Newcomers Club. We met lots of people who came to the "Choice City" after retiring and heard of one who subsequently lost a spouse to the disease.

After that I paid a lot more attention to the entity. As I read considerably more about NF, I realized that streptococcal infections weren't its only cause, but I'll focus on strep today.

NF isn't the only major complication caused by Group A streptococci (GAS). There's a toxin-caused deadly illness called toxic shock syndrome. This has been around in the medical literature for about three decades. I became aware of it in December 1980 when the New England Journal of Medicine published an article describing 38 cases of this dire syndrome where patients, usually women who were menstruating and using tampons, developed high fever, low blood pressure and multi-organ failure, as well as sloughing off the skin of their palms and soles. The causative agent often was staph and blood cultures were often positive for staphylococci.

Yet half of the cases in a 2010 review did not involve menstruating women, in fact a quarter of the patents were men. Over the past thirty years, tampons have been improved so that the number of cases invoking their use has gone down markedly.

But the syndrome is still around and other bacteria, especially GAS, have been involved. Many of the patents who developed strep-associated toxic shock syndrome (STSS) had underlying chronic diseases (e.g., diabetes, cancer or alcoholism) or had recent surgical procedures. Some researchers have implicated a specific toxin in strep TSS.

When GAS bacteria find their way into areas where they are rarely seen, they can cause diseases much more severe than the usual strep throat or skin infections. These illnesses are called "invasive group A streptococcal disease."

It's estimated that an average of 10,000 cases of invasive GAS disease with a mortality rate over 10% happen in our country every year. Necrotizing fasciitis and STTS are even more likely to be lethal. A fifth to a quarter of those who develop NF die and half of those who have STTS.

Remember most of the millions of cases of strep infections that occur yearly here are relatively mild, but even those are nothing to be ignored. Good hand washing technique is crucial and I've provided you a link to the Mayo Clinic's article on thus subject.

The CDC article stresses that anyone who develops an infected wound, particularly if they also have a fever, should see a physician immediately. You may save your life if you do so.

 

The PANDAS controversies

Thursday, December 22nd, 2011

We're not talking about this kind of Panda

The more I read about the relatively new syndrome PANDAS, Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus, the more I realize how complex the issues are that surround it. We appear to be entering a new field of medicine, one that holds enormous potential for unlocking the root causes of baffling problems in neurology and psychiatry

The story starts in the mid 1990s when Dr. Susan Swedo, now Chief of the National Institute of Mental Health's (NIMH)  Pediatrics & Developmental Neuroscience Branch , reported that childhood obsessive-compulsive disorder (OCD) may sometimes be triggered by a strep infection.  OCD may involve compulsive handwashing, twenty or thirty times a day; it can manifest itself as a need to have things "just so" in order to relieve anxiety, repeating and checking behavior, counting and arranging objects or clothing, hoarding, praying, reading a section of a story over and over again.

Some of these youngsters also have tics, involuntary movement disorders. Another subset just has tics, but no OCD.

A moving portrait of a child who fits this profile was published in the Los Angeles Times early this month. The boy involved wa a normal eleven-year-old sixth grader until he developed a strep throat. Then his behavior altered to the point where daily life seemed totally changed; he became obsessed with being clean  and afraid of germs to the point where he was unable to go back to school.

Increasingly these diseases and perhaps others are being linked by some eminent researchers to strep infections. A senior immunologist at the University of Oklahoma College of Medicine thinks the mechanism of PANDAS involves antibodies, released in response to a strep infection, that can bind to brain cells and cause the release of dopamine, a brain chemical which in excess, may be linked to OCD and tics. The diagnosis, at the moment, is strictly clinical; there is no lab test to confirm that a child has PANDAS.

One form of OCD involves repetitive handwashing

Many youngsters with OCD and/or tics don't appear to have this strep-related syndrome and some equally prominent academic physicians feel kids can have a mental health/neurological disorder first and just have it exacerbated by strep throat or other infections. Others want to treat the most severely affected of these children with antibiotics even if they don't have an active strep infection.

The NIMH makes the point that these children, as opposed to others with OCD and/or tics, have an abrupt worsening of their symptoms when they have a strep infection. They then will have a slowly improving course after a few weeks or months.

The guidelines are admittedly vague; NIMH says PANDAS can be "identified after two or three episodes of OCD or tics that occur in conjunction with strep infection."

A senior Harvard professor of psychiatry who is the head of the International OCD Foundation's scientific advisory board has been quoted as saying the portion of OCD linked to PANDAS is "exceedingly common."

Is this the tip of an iceberg of neuropsychiatric problems linked to infections? Only time and lots of research will tell.